Air dehydrator



June 21, 1932. H. B. HAR MAN 6 1,863,656

6 AIR DEHYDRATOR\ Filed Oct. 10. 19:50 4 Sheets-Sheet 1 I 1111B aprimw,

June 21, 1932. I,

H. B. HARTMAN AIR DEHYDRATOR Filed Oct. 10. 1930 4 Sheets-Sheet 2 I I II I I!!! III I II I II I

H fim g j June 21, 1932. B HARTMAN 1,863,656

AIR DEHYDRATOR Filed Oct. 10, 1930 4 Sheets-Sheet 3 Jwumtoz Eli-Hartman,

June 21, 1932- A A 1,863,656

AIR DEHYDRATQR Filed Oct. 10. 1930 4 Sheets-Sheet 4 gwoemkw H.B.Harfman,

Patented June 21, 1932 HARRY BUXTON HARTMAN, OF BUFFALO, NEW YORK AIR :onn rmwron Application filed October 10, 1930. Serial No. 487,878.

,This invention relates to air dehydrators, and has for one of its objects to provide an improved dehydrator structure of U comparatively simple cosntruction and relatively low installation cost and which has an improved mode of operation designed to effect the dehydration of air rapidly and economically. I Another object of the invention is to pro- 1g vide improved means for reactivating the dehydrating material rapidly and economicallyand without the necessity of dismantling any part of the dehydrator structure.

Another object of the invention is to provide automatic means to operate an alarm signal in the event reactivation of the dehydrating material has not been effected when reactivation of such material is required, to provide simple means manually 2o operable to initiate reactivation of the dehydrating material, and to provide other means automatically operable to haltthe reactivating process when reactivation of the dehydrating material has been effected.

I With the foregoing and other objects in view, which will become more fully apparent as the nature of the invention is better understood, the same consists in the novel features of construction, and inthe novel combination and arrangement of parts, as

will be hereinafter more fullydescribed, illustrated in the accompan ing drawings and defined in the appended claims.

In the drawings, wherein like characters of reference denote corresponding parts in the different views F ig.. 1 is a central vertical sectional view through an air dehydrating apparatus constructedin acc rdance with one practical embodiment of the'invention.

Fig. 2 is a horizontal sectional view through the apparatus.

Fig. 3 is a side elevation: of a two-unit 4 dehydrator constructed in accordance with the invention.

' Fig. 4is an enlarged longitudinal sectional view. through the device for automatically closing the indicator circuit when the dehydrating material is in need of reactivation.

Fig. 5 is another longitudinal sectional view through the device shown in Fig. 4.

Fig. 6 is a cross section on the line 66 of Fig. 4.

Fig. 7 is a plan view of the air distributing plate shown in Fig. 4.

Fig. 8 is a vertical section through the air heating device shown in Figs. 1 and 3.

Fig. 9 is a section through the heating device at right angles to Fig. 8" and Fig. 10 is a bottom view of the heatin device with the bottom cover plate thereo removed. 1

Referring first to the embodiment of the apparatus illustrated in Fig. 1 of the drawings, l0 designates a closed tank or vessel containing the deli dratin'g material designated as 11. Preferably, but not necessarily, this tank or vessel 10is of cylindrical shape and is disposed in an u right position, being supported, for examp e, on legs 12. Within said tank are horizontally disposed foraminous portions 13 and 14 located, respectively, in spaced relation to the bottom and the top walls 15 and 16 of the tank, the dehydrat- 7 i g material 11 being confined between these two portions as shown.

Connected with the bottom of the tank 10 is an air inlet pipe 17 having a regulating or cut off valve 18 interposed therein, while connected with the top of said tank is an outlet pipe 19 for the deh drated air, said outlet pipe'having a regu ating or cut off valve 19 interposed therein. The air, as is understood, enters the tank 10 at the bottom 35 thereof through the pipe 17, passes upward through the screen or partition 13, through the dehydratingmaterial 11 which extracts the moisture therefrom, thence through the screen or partition 14 and out of the tank 9 through the pipe 19.

Adapted for cooperation with the tank 10 is a heat insulator composed preferably of a pair of sections which are movableeither to a position substantially completely "enclosing 05 said tank to prevent cooling thereof by the ambient air and to confine heat therein, or to an o 11 position ermitting the ambient air to e" ect cooling 0 said tank. In the pres;

ent instance said insulator is composed of a pair of sections 20, 20 which are of semicircular shape and hinged together at adjacent longitudinal edges whereby they may be swung to a closed position closely surrounding the tank 10, or to an open position spaced from said tank, a coil spring or springs 21 associated with the sections where they are hinged or other suitable means being provided to tend constantly to ur e said sections toward their open position. bviously, said sections may be mounted in any suitable manner for cooperation with the tank 10. For example, lugs 22 may be provided on the tank, and the hinge pin 23 of the sections may be journaled in said lugs.

When it is desired to reactivate the dehydrating material 11 the sections 20-20 are adapted to be moved manually to a closed position surrounding the tank 10, in which position they are adapted to be held, during the reactivating period, by means which is automatically releasable upon completion of the reactivating process to permit said sections to be automatically swung open by the spring or springs 21, said holding means consisting, for example, of an intermediately pivoted latch 24 having one end formed to embrace a pair of lugs or projections 25, 25 on the sections 20, 20, respectively, when said sections are closed to hold them closed, as illustrated in Fig. 2 of the drawings, and an electro-magnet 26 which, when energized,-

cooperates with the other end of said latch to eiiect ivotal movement thereof to disengage its rst mentioned end from said lugs or projections.

Suitably mounted in juxtaposition to the tank 10 is an air heating device composed in this instance of a heat insulating casing 27 having suitably mounted therein one or more electrical heating units 28, which unit or units may be of any suitable or well known commercial type. Connected with one end of the casing 27 is an air inlet pipe 29 having a control valve 30 interposed therein, while connecting the other end of said casing with the topportion of the tank 10 above the screen or partition 14, is an air conduit 31 which preferably is heat insulated as shown.

In connection with air conduit 31, it will be observed from Figure 1 of the drawings that the open end thereof is disposed toward the end 16 of the tank, and, for the purpose of securing a more effective distribution of the air passing through the conduit a plate or defiector 31a may be employed. This plate 31a may be held to the mouth of the pipe 31 by the use of a suitable nipple insulated ip the mouth of the pipe and a lock nut to cooperate with the nipple to clamp the distributer plate in position. This plate will deflect the air from the immediate center of the tank into a circle midway of the center of the dehydrating material and the side of the easing. The edge of the plate 31a may be formed with a plurality of points or reen trant notches which will have the eflect of breaking up and distributing the air in a more eifective manner thereby to more evenly act on the material to be reactivated especially when the pump 32 is sucking or drawing air through the material from the bottom of the tank, the heated air, of course, issuing from the mouth of the pipe 31. An example of the manner of forming the edge of the plate 31a is illustrated in Figure 7. It will, of course, be understood that the shape of the reentrant notches may be varied to produce any desired edge configuration for the plate.

As is ap arent air in its travel through the casing 27 50m the pipe.29 to the conduit 31, will be heated by the electrical heating unit or units 28 if current is supplied to said unit or units.

At 32 is designated an air suction fan which is adapted to be driven by an electric motor 33 and which is connected with the bottom of the tank 10, below the screen or partition 13, by a pipe 34 having a control valve 35 interposed therein. As shown, the pipe 34 extends transversely with respect to the tank 10 substantiall entirely thereacross, and within the tan is provided one or more narrow, longitudinally extending slots 36 through which air is adapted to be drawn from the tank by the fan 32.

The alarm device to automatically produce a warning signal in the event reactivation of the dehydrating material has not been effected when required, consists in the present instance of an electric bell or other audible or visual signal device 37 included in circuit with an automatic switch device disposed at a convenient location within the tank 10.-

This switch device which may be of any suitable or preferred construction, is shown in detail in Figs. 4 to 6 of the drawings, and consists, preferably, of a plug 38 threaded into an opening in the side of the tank 10 and carrying a tube 39 which is closed at its inner end and has formed therein a plurality of transverse kirfs or narrow slots 40 which serve to permit air to pass through said tube and at the same time to exclude therefrom the reactivatin material which surrounds the tube. Held within the outer end portion of said tube by a cap 41 threaded on the plug 38, is a body of insulating material 42 in which are embedded the outer end portions of a pair of switch arms 43, 43, which switch arms extend into the tube 39 and through the inherent resiliency of either or both of the same, i

of a small body 44 of calcium chloride or equivalent material interposed between a pair of insulating plates '45 of glass or the like clipped to the respective switch arms.

Also extending into the tank 10 and surwhile the automatic alarm circuit closing.

switch device heretofore described preferably is located near the top of said tank. a

At 47 is diagrammatically illustrated and designated generally an automatic cut-out switch of a well known commercial design interposed between the current supply wires w and having connections with the electromagnet 26, the heating unit or units 28, thd' motor 33 and the thermostat 46, it being sufficient to state in respect to this switch, inasmuch as it is known commercially and forms per se no part of the present invention, that it is adapted to be manuall closed and when closed, closes the circuits t rough the motor 33 and the heating unit or units 28, and that it is adapted to operate automatically when the holding circuit through the thermostat 46 is opened to momentarily close the normally open circuit through the electro-magnet 26 and open the circuits through the heating unit or units 28 and the motor 33.

In view of the foregoing, the model of op eration of the apparatus will be apparent and is as follows: Normally the insulating casing sections 20, are disposed in a position swung outward from the tank 10 to permit cooling of the tank by the ambient air, the valves 30 and are closed and the valves 18 and 19 are open, permitting flow'of air from the pipe .17 through the dehydrating material 11 to the pipe 19, which latter pipe may be connectedwith an ozone generator or other apparatus using dry air, and the automatic switch 47 is open, cutting off current from electro-magn'et 26, the heating unit or units 28 and the motor 33. Thus, air passing from the pipe 17 to the pipe 19 through the dehydrating material 11 contained in the in terposed tank 10 will be dehydrated by said material. Following a certain period of operation of the apparatus, which period will depend upon the moisture content of the air undergoing dehydration, and upon the moisture absorption quality of the dehydrating material 11, as well as upon temperature conditions, the dehydrating material .will become moist and lose some or all of its dehydrating efi'ectiveness, at or prior to which time said material should be reactivated, that is, the accumulated moisture therein should be driven therefrom. If the attendant is alert and operates the apparatus to reactivate the material at regular intervals or when required, the automatic signal 37 will not be actuated. If, however, through neglect of the attendant, or by reason of any other cause, the reactivation of the material 11 is not efi'ected when required, the accumulating moisture in the tank 10 will finally melt the body of calcium chloride or other material 44 holdin the switch arms 43, 43 normally spaced rom one another and this will permit said switch arms to move together, closing the circuit through the bell or other signal device 37 and causing the latter to produce an alarm indicating that the material 11 is in need of reactivation, the material 44 being such asto melt and permit closing of the alarm circuit sufficiently prior to the material 11 completely losing its dehydrating eiiicien'cy to afford ample time Within which to complete a run of the apparatus.

Reactivation of the dehydrating material 11 and automatic stop-ping of the reactivating rocess' is accomplished as follows: The ins ating cover sections 20, 20 for the tank 10 are swung inward in close surrounding relation to said tank and are secured in this relation by engagement of the latch 24 with the lugs or projections 25, the valves 18 and 19' are closed and the valves 30 and 35 opened, and the automatic-switch 47 is closed, thereby placing the thermostat 46 in controlling re lation to said switch and at the same time closing the circuits through the heating unit or units 28 and themotor 33. As a result, a circulation of air is effected by the fan 32 through the pipe 29, the heater casing 27 and the pipe 31, downward through the moist dehydrating material 11, and through the slots 36 in the pipe 34 into said pipe and through the latter and the tan 32 to the atmosphere. This air in its travel through the heater casing 27 is dried and heated by the unit or units 28 and therefore serves to extract moisture from the material 11 in its passage through said material. As the .reactivating process is continued and all or substantially all of the moisture is extracted from the material 11, a rise in temperature obviously will take place within the tank 10, which rise in temperature is greatly facilitated by the insulating sections 20, 20 disposed in surrounding relation to the tank, and when finally the temperature rises to a predetermined degree, the thermostat 46 operates to open its related circuit controlling the switch 47. Upon opening of the thermostat circuit the switch 4lautomatically operates to momentarily close the circuit through the electro-magnet 26 with the result that said magnet operates to effect release of the latch 24, thereby allowing the tank insulating sections 20, 20 to be swung automatically outward by the springs 21.

Immediately thereafter, the switch 47 operates to open the circuits through. the heating unit or units 28 and the motor 33, thereby automatically stopping the reactivating process, whereupon the valves 30 and 35 are adapted to be closed and the valves 18 and 19' opened to reestablish the original status of the apparatus.

In the event of operation of the alarm 37 by melting of the'material 44 and consequent automatic closing of the switch constituted by the arms 43, 43, it will be necessary to remove the switch from the tank 10 and replace the melted material 44, which may be done at any convenient time.

With respect to the present apparatus it will be observed that the air undergoing de hydration travels from the bottom of the tank 10 upward through the material 11, while the hot air for effecting reactivation of said material travels from the top of the tank downward through said material; In prior ty s of air dehydrators, the general practice as been to blow the reactivating air through the dehydrating material in the same direction asthe direction of. travel of the air to be dehydrated, which means, of course, that since the greatest accumulation of moisture in the dehydrating material is in the portion of'said material where the air enters the same, this moisture is carried with the reactivating air through the less moist portions of the dehydrating material, thereby requiring a major amount of time and requiring the expenditure of a major amount of heat and power to effect reactivation. On the other hand, by reason of the present arrangement whereby the reactivatin air is caused to travel through the dehy rating material in a direction opposite to the direction of travel of the air to be dehydrated by said material, the moisture in that position of the dehydrating material having the greatest accumulation of moisture is not carried by the reactivating air through the remaining portion of the dehydrating material and as a consequence the present apparatus effects reactivation in a minor amount of time and with the expenditure of only a minor amount of heat and power.

With respect to the device for heating" the reactivating air, it will be observed that the casing 27 is provided at opposite sides thereof with retaining grooves 48 for the side edges of a plate 49 which carries a suitable insulating base or socket formations 50 in which the heating unit or units 28 is or are threaded, the plate 49 being spaced slightly from one of the side walls of the casing 27 to afford a space for the accommodation of the circuit wires leading to the heating unit or units, said wires extending from the casing 27 through an insulating bushing 51 threaded in a-wall of the casing. Preferably a plurality of heating units 28 connected either in series or in arallel, as may be deemed most desirable un er given conditions, are pro vided, and in order that the plate 49 which carries the insulating base or sockets in which said heating units are threaded, may readily be removed from and inserted into the casing 27, one of the walls of said casing is removable. In the present instance the grooves 48 extend vertically and the bottom wall 52 of the casing is rem vable, the plate 49 therefore being adapted for sliding move ment either into or from the casing through the open bottom thereof when the wall 52 is removed.

The slot or slots 36 in the pipe 34 provide means whereby reactivating air is drawn through all portions of the dehydrating material especially at the bottom of said material, while in order to assure that the hot reactivating air entering the top of the tank 10 through the conduit 31 will pass downward throughout substantially the entire mass of the dehydrating material, especially the entire top portion of said mass, the said conduit is terminated approximately centrally of the tank 10 and at its end is upwardly directed as shown.

In Fig. 3 of the drawings is illustrated a practicable way in which two dehydrating units similar to the single unit heretofore described may be connected together for joint operation, to efiect a continuous supply of dehydrated air. According to this embodiment of the invention the two units are so connected that the dehydrating material in one unit may be reactivated during air dehydrating operation of the other unit, and vice-versa, and in this connection the arrangement is such that only a single fan and motor, a single heating device for the reactivating air, and a single electro-ma net and automatic switch is required for 0th units.

In the two Fig. 3, 10a, 10b, designate, respectively the two dehydrating material containing tanks of the two unit apparatus, these tanks being duplicates of one'enother and of the tank 10 heretofore described, each of said tanks having associated therewith a heat insulating casing 20a embodying sections operable in the same manner as the sections 20, 20.

The two tanks 10a, 101) are disposed in suitable spaced side to side relation with the sections of the respective insulatin casings 20a arranged to meet at adjacent si es of the respective tanks when said sections are closed. At their lower ends the tanks 10a, 106 are connected together by a common air inlet pipe 171: having a three-way valve 18a interposed therein so that air to be dehydrated may be admitted to either of said tanks and cut ofi from the other tank. In a similar manner, the tops of said tanks 10a, 10?; are

unit apparatus illustrated in i ozone generator or other apparatus with.

so that communication of either tank with the which said pipe 19a is connected, may be established and communication of the other tank with said generator or apparatus may be cut off. I

The single air heating device used inconnection with the two unit apparatus is designated generally as 27 a and is or may be of the same construction as the heating device heretofore described. It. preferably is located between the two tanks 10a, 10b and is connected by a common hot air outlet pipe or conduit 31d with each of said tanks, this pipe or conduit 31d having either a single three-way valve, or a pair of cut oil valves 31?), 310 interposed therein so that the supply of hot air may be directed to either tank and be cut off from the other tank.

Extendin downward from the bottom of the casing 2 a of the heating device is an air inlet pipe 29a in which is interposed a control valve 30a, and on this pipe or on any other suitable support which may be provided midway between the tanks 10a, 10b, is mounted a swingable arm carrying a latch 24a and a latch releasing electro-magnet 26a.

Connecting the bottom portions of the tanks 10a, 10b is a common outlet pipe 34a for the reactivating air, while connected with said pipe through a three-way valve 35a is a suction fan 32a which is adapted to be driven by a motor 3361:.

Each tank has associated therewith an au-' tomatic alarm circuit closing switch similar to the corresponding switch heretofore described, and these switches are connected with a common signal device 37a so that closing ofeither switch is effective to operate said signal device. Moreover, each tank is provided with a thermostatic control switch 46a in controlling relation to an automatic cut out switch (not illustrated) similar to the switch 47 and connected with the heating unit or units of the heating device 27a, the motor 33a and the electro magnet 26a in the manner heretofore described in connection with the single unit embodiment of the invention.

" In view of the foregoing, the operation of the two unit apparatus will be readily apparent. The valves 18a and 19?) are adapted to be adjusted to permit air to be dehydrated to flow through one of the tanks 10a or 106 and to prevent such air from flowing through the other of said tanks. The sections of the insulating covering 20a of the tank through which air being dehydrated is flowing, are open, while the sections of the insulating covering of the other tank are closed, being held closed by the latch 24a which is swingable for cooperation with the sections of the covering for either tank. The valves 31?) and 310 are adjusted to cut oil the air supply from the heating element 27a to the tank in which dehydration is taking place and to admit air from said heating device to the other of said tanks. The valve 85a is adjusted to cut off communication between the fan 32a and the tank in which dehydration is taking place and toestablish communication between said fan and the other of said tanks. If now, the automatic cut-out switch not shown) is closed, the heating units inthe heating device 27a will be heated and the motor 33 will be set in operation to draw air through the tank not being used for dehydration, thereby to effect reactivation of the dehydrating material contained in said tank. When reactivation has been completed, the thermostatic switch 46a related to the tank in which reactivation is taking place, will automatically open its related cut out switch'control circuit with the effect of causing said out out switch to momentarily energize the electro-magnet 26a to release the latch 24a, and at the same time open the heating device and. the motor circuits. It is then intended that the respective valves be adjusted to reverse the status of the apparatus and that the sections of the insulating casing 20a of the tank in which dehydration had last been taking place, be closed and latched closed by the latch 241a which may readily be swung for cooperation with said sections. The apparatus thus is in readinessto efiiectreactivation of the dehydrating material in the tank last used for dehydration upon closing of the automatic cutout switch, the other tank in the meantime being capable of use for dehydrating purposes. Upon completion of reactivation of the material in the second tank the automatic operation just described is repeated. Thus,

a substantially continuous supply of dehym5 drated air may be produced employing the tanks 10a and 10b alternatively for dehydrating operation, and when either tank is being used to dehydrate air, the dehydrating material in the other tank may be reactivated.

Without further description it is thought that the features and advantages of the in-. vention will be readily apparent to those skilled in the art, and it will of course be understood that changes in the form, propor- 115 tion and minor details of construction'may be resorted to, without departing from the spirit of the invention and scope of the appended claims.

I claim 1. An air dehydrator comprising a tank containing air dehydrating material, means for the passage of air to be dehydrated through said tank, means for causing a flow of dehydrating material reactivating air 125 through said tank, a heat insulating casing for said tank, means constantly tending to move said casing to a position to permit contact of the ambient air with said tank, releasable means to hold said casing in a posi- 180 .for said tank, means constantly tending to move said casing to a position to permit contact of the ambient air with said tank, releasable latch means to hold said casing in a position closely engaging said tank to exclude the ambient. air from contact therewith, an electro-magnet operable when energized to effect release of said latch means, and means automatically operable upon reactivation of said dehydrating material to efi'ect closing of the circuit in which said electro-magnet is included.

3. An air dehydrator comprising a tank containing air dehydrating material, means for the passage of air to be dehydrated through said tank, electrically operated means for causing a How of dehydrating material reactivating air through said tank, electrical heating means for the reactivating air, a sectional heat insulating casing for said tank, means constantly tending to move the sections of said casing to an open position spaced from said tank, electrically releasable means for holding said sections in a closed position closely embracing said tank, and means'automatically operable upon reactivation of the dehydrating material to close the circuit in which said releasable means is included and to open the circuits in which said power means and said heating means are included.

4. An air dehydrator comprising a tank containing air dehydrating material, means for the passage of air to be dehydrated through said tank, means for causing a flow of dehydrating material reactivating air through said tank, a heat insulating casing for said tank movable between a position closely embracing said tank to exclude the ambient air therefrom and a position spaced from said tankto permit contact of the ambient air with the tank, means for holding said casing in the first mentioned position, means operable automatically upon reactivation of the dehydrating material to release the holding means for said casing, and means operable upon release of said holding means to move said casing to the second mentioned position.

5. An air dehydrator comprising a tank containing air dehydrating material, means for the passage of air to be dehydrated through said tank, means for causing a flow of dehydrating material reactivating. air

through said tank, a heat insulating casing for said tank movable between a position closely embracing said tank to exclude the ambient air therefrom and a position spaced from said tank to permit contact of the ambient air with the tank, and means operable automatically upon reactivation of the dehydrating material to move said casing from its first mentioned position to its second mentioned position.

6. In an air dehydrator, a tank containing air dehydrating material, means for the passage of the air .to be dehydrated through said tank, means for the passage of dehydrating material reactivating air through said tank, and a heat insulating casin adapted to embrace said tank during reactivation of the dehydrating material and to be disposed in spaced relation to said tank during air dehydrating operation of the dehydrator, said heat insulating casing comprising a pair of cooperating sections hinged to the tank, latch means for holding said sections in a position embracing said tank, and spring means operable to swing said sections away from the tank upon release of said latch means.

7 Air dehydrating apparatus comprising a pair of tanks each containing air dehydrating material, means for admittin air to be dehydrated to either tank and for enying the admission of such air to the other tank, means for the admission of dehydrating material reactivating air to either tank and for denying the admission of such air to the other tank, reactivating air circulatin means for selective connection with said ta s, a pair of heat insulating casings individual, respectively, to said tanks, each casing being movable to a position to closely embrace its related tank and being automatically movable to a position spacedifrom its related tank, a single electrically releasable latch device effective to hold either casing in embracing relation to its related tank, and means associated with each tank and connected with said latch device operable upon reactivation of the dehydrating material in either tank to effect release of said latch device.

8. Air dehydrating apparatus comprlsing a pair of tanks each containin air dehydrating material, means for admitting air to be dehydrated to either tank and for denly-ing the admission of such air to the other tan means for the admission of dehydrating material reactivating air to either tank and for denying the admission of such air to the other tank, an electrical device for heata ing the reactivating air, a pair of heat insulating casings individual, respectively to said tanks, each casing being movable to a position to closely embrace its related tank and being automatically movable to a position spaced from its related tank, a single electrically releasable latch device efl'ectiveto hold either casing in embracing relation to its related tank, and means automatically operable upon reactivation of the dehydrating' material in either tank to release said latch device and to open the circuits in which said heating device and said reactivating air circulating means are included. In testimony whereof I hereunto afiix my signature.

HARRY BUXTON HARTMAN. v 

